The current 5"/38 Mk.30 mounts are too large both height and lengthwise (off by 5-6 pixels in places).
mmmm 5-6 pixels? You sure you were using correct gun
here is your drawing, my older one and yours placed above my "bigger"
Mine is about one pixel too tall and one pixel too wide. Back when i drew it, I wasen't using Paint.net for scaling so such inaccuraties migth be down there more.
As comes for the style of the actuall shading, Yours present the old and unfortuanetly sort of obsolete way of shading rounded edges. There is a guide I made more than year ago in the
shading guide
So IMO best rendition of this gun that I agree is the most iconic of all naval guns, would come if you would shade the edges of your correct size version instead of displaying the dark grey lines.